PJH Studios

Tag: oceanography

  • There’s a whale graveyard

    Along a stretch of the Indian Ocean, there’s a whale graveyard.

    Here we report the discovery of a vast whale necropolis in the Diamantina Zone (4,616- to 7,001-m depth), extending about 1,200 km along the sea floor of the southeastern Indian Ocean. This area has a deep and extensive accumulation comprising five modern natural whale-fall communities and 476 fossil cetaceans recorded. We show that carcasses host specialized communities dominated by brittle stars, bone-boring worms and chemosynthesis-based bivalves and that the fossil record in this area comprises both extant and extinct deep-diving beaked whales. Isotopic dating shows that whale falls in this region have occurred since at least 5.3 million years ago. These findings reshape the understanding of the limits and biogeography of whale-fall ecosystems and establish some deep sea floors as a fossil archive for tracing cetacean evolution over geological time.

  • Here’s to the Greenland shark

    We’ve all heard about the Greenland shark, which has probably been swimming around for over 400 years. But what how’s do we know about this creature of the deep?

    The Greenland shark is slow, as befits a fish so venerable. At full speed and with strenuous effort, it moves somewhere between 1.7 and 2.2 mph. Although one of the two largest flesh-eating creatures in the sea, it has an astonishingly slow metabolism; in order to survive, a 200-kilo shark has to consume the calorific equivalent of one and a half chocolate digestives a day. They are both hunters and scavengers; they have been thought to hunt seals, perhaps inhaling them as they sleep on the surface of the water, but largely they eat whatever falls off the ice: reindeer, polar bears. The leg of a man was found in one shark’s stomach, but none of the rest of him.

    Plus, we don’t know how many there are.